Tuesday, May 24, 2022

[Paleontology • 2022] Thanatosdrakon amaru • A Giant Azhdarchid Pterosaur (Pterosauria: Azhdarchidae) from the Upper Cretaceous of Argentina

Thanatosdrakon amaru
 Ortiz David, González Riga & Kellner, 2022

Artwork by Khang Nguyễn An

The largest pterosaur discovered in South America and one of the largest flying vertebrates in the world is described. Thanatosdrakon amaru gen. et sp. nov. is a new azhdarchid found in the upper-most levels of the Plottier Formation (upper Coniacian–lower Santonian, Neuquén Basin), Mendoza, Argentina. Two specimens were identified, the holotype (UNCUYO-LD 307) and the paratype, with an estimated wingspan of ∼ 7 m and ∼ 9 m, respectively. The cladistic analysis, based on 216 characters and 97 taxa, recovered Thanatosdrakon deeply nested within Azhdarchidae. Relationships within this clade are well resolved and the clade Quetzalcoatlinae presents two well-defined sister-groups: (Arambourgiania, Mistralazhdarcho, Aerotitan, Hatzegopteryx, Albadraco) + (Cryodrakon, Thanatosdrakon, Quetzalcoatlus ssp.). Thanatosdrakon is the oldest taxon of the clade Quetzalcoatlinae so far. It is represented by several well-preserved axial and appendicular bones in three dimensions. Some of these elements have never been described in giant azhdarchids (e.g. complete norarium, dorsosacral vertebrae and caudal vertebra) and this allows to expand the knowledge about the anatomy of this diverse group of pterosaurs. Finally, from a paleoecological point of view, Thanatosdrakon was found in floodplain deposits of ephemeral meandering systems indicating that this large flying species inhabited continental environments.

Keywords: Thanatosdrakon, Azhdarchidae, Neuquén Basin, Plottier Formation, Upper Cretaceous, Argentina

Thanatosdrakon amaru gen. et sp. nov.

Leonardo D. Ortiz David, Bernardo J. González Riga and Alexander W.A. Kellner. 2022. Thanatosdrakon amaru, gen. et sp. nov., A Giant Azhdarchid Pterosaur from the Upper Cretaceous of Argentina. Cretaceous Research. 137, 105228. 105228. DOI: 10.1016/j.cretres.2022.105228

Thanatosdrakon amaru: el pterosaurio más grande de Sudamérica
El descubrimiento, liderado por el investigador de la UNCUYO y de Conicet Leonardo Ortiz David, brinda información novedosa sobre la evolución de estos vertebrados voladores que alcanzaron 9 metros de envergadura y convivieron con los dinosaurios durante el Cretácico.